<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="jquery.min.js"></script>
    <style>
        div {
            width: 200px;
            height: 200px;
            background-color: pink;
        }
    </style>
</head>
<body>
    <div></div>
    <span></span>

    <script>
        //对象不同
        let div1 = document.querySelector('div');
        let span1 = document.querySelector('span');
        console.log(div1);
        console.log(span1);
        console.log($('div'));
        console.log($('sapn'));
        div1.style.backgroundColor = 'blue';

        //jquery对象和dom对象可以相互转换

        //dom对象转换成jquery对象
        $(div1); //将dom对象外层封装成jquery对象
        //jquery转换成dom对象（jquery像是列表）
        $('div')[0];
        $('span').get(0);
    </script>
</body>
</html>